Home
Class 12
CHEMISTRY
If the half-cell reactions are given as ...

If the half-cell reactions are given as
(i)`Fe^(2+) + 2e^(-) to Fe(s),E^@ = -0.44 V`
(ii) `2H^(+)(aq) + O_2(g) + 2e to H_2O (l) , E^(@)= + 1.23V`
The `E^@` for the reaction
`Fe(s) + 2H^(+) + O_2(g) to Fe^(2+)(aq) + H_2O(l)`

A

`+1.67V`

B

`-1.67V`

C

`+0.79V`

D

`-0.79V`

Text Solution

Verified by Experts

The correct Answer is:
A
`E^(@)=1.2-(-0.44)=1.67V`
Promotional Banner

Similar Questions

Explore conceptually related problems

If the half cel reactions are given as (i) Fe^(2+)(Aq)+2e^(-)rarr Fe(s),E^(@)=-0.44 V (ii) 2H^(+)(sq)+1/2 O_(2)(g)+2e^(-)rarrH_(2)O(l) E^(@)=+1.23 V The E^(@) for the reaction Fe(s)+2H^(+)+1/2O_(2)(g)rarrFe^(2+)(aq)+H_(2)O(l) will be

Standard oxidation potential for the following half-cell reactions are [Fe(s) rarr Fe^(2+)(aq) + 2e^(-) E^3 = +0.44 V] [Co(s)rarr Co^(3+) (aq) + 3e^(-) E^0 = - 1.81 V The standard emf of the cell reaction [3Fe(s) +2Co^(3+) (aq)rarr 3Fe^(2+) (aq) + 2Co(s)] , will be

The standard oxidation potentials, , for the half reactions are as follows : Zn rightarrow Zn^(2+) + 2e^(-) , E^(@) = +0.76V Fe rightarrow Fe^(2+)+ 2e^(-), E^(@) = + 0.41 V The EMF for the cell reaction, Fe^(2+) + Zn rightarrow Zn^(2+) + Fe

The half cell reactions for rusting of iron are : 2H^(+) + 2e^(-) + (1)/(2)O_(2) rightarrow H_(2)O (l) , E^(@) = +1.23V Fe^(2+) + 2e^(-) rightarrow Fe , E^(@) = -0.44V Delta^(@) ((inKJ) for the reaction is : Fe+2H^(+) + (1)/(2) O_(2)rightarrow Fe^(+2)+ H_(2) O ((l))

Given electrode potentials: Fe^(3+) + e^(-) rarr Fe^(2+) : E^(o) =0.771 V and I_(2) 2e^(-) rarr 2I^(-), E^(o) = 0.556 V then E^(o) for the cell reaction 2 Fe^(3+) 2I ^(-) rarr 2 Fe^(2+) + l_(2) will be:

The standard reduction potentials at 298K for the following half cells are given : ZN^(2+)(aq)+ 2e^(-)Zn(s) , E^(@) = - 0.762V Cr^(3+)(aq)+ 3e^(-) Cr(s) , E^(@) = - 0.740V 2H^(+) (aq)+2e^(-) H_(2)(g) , E^(@)= 0.000V Fe^(3+)(aq)+ e^(-) Fe^(2+)(aq) , E^(@) = 0.770V which is the strongest reducing agent ?

The standard electrode potential of the half cells are given below : Zn^(2+)+ 2e^(-) rarr Zn(s), E^(o) = - 7.62 V Fe^(2+) + 2e^(-) rarr Fe(s) , E^(o) = -7 .81 V The emf of the cell Fe^(2+) + Zn rarr Zn^(2+) + Fe will be :

Potential for some half cell reactions are given below. On the basis of these mark the correct answer. (i) H^(+)(aq) + e^(-) rightarrow (1/2)H^(2)(g) E_(cell)^(@) = 0.00V (ii) 2H_(2)O(l) rightarrow O_(2)(g) + 4H^(+)(aq) + 4e^(-) , E_(cell) = 1.23V (iii) 2SO_(4)^(2-)(aq) rightarrow S_(2)O_(8)^(2-)(aq) + 2e^(-), E_(cell)^(@) = 1.96V

For the reactions {:(MnO_(4)^(-)+8H^(+)+5e^(-)rarr Mn^(2+)4H_(2)O","E^(o) = + 1.51 V),(MnO_(2)+4H^(+)+ 2e^(-) rarr Mn^(2+)+2H_(2)O"," E^(o)= + 1.23 V ):} then for the reaction : MnO_(4)^(-) + 4H^(+) + 3e^(-) rarr MnO_(2)+2H_(2)O","E^(o)

If E_(Fe^(2+))^(@)//Fe = -0.441 V and E_(Fe^(3+))^(@)//Fe^(2+) = 0.771 V The standard EMF of the reaction Fe+2Fe^(3+) rarr 3Fe^(2+) will be: